Electrical apparatus



April 22, 1952 A. w. ALBRECHT 2,594,111

ELECTRICAL APPARATUS Filed Dec. 14, 1949 as a 39 22 l Patented Apr. 22, 1952 Albert W. Albrecht, McHenry, Ill.,- assignor to Oak Mfg. Co... Chicago. Ill., a corporation of Illinois Application December 14, 1949.. SerialN. 132,839

(Cl. 200e-6) l Claim.

This invention relates to an electrical appa ratus. and particularly to a tuner constructionI for use with high frequency circuits such as are` encountered in television. The invention pertains to that type of tuner wherein a turret or head may be indexed to a number of positions,v each position providing for tuned circuits being connected to the television receiver or other device.

High frequency tuners require excellent contacts in order to maintain low ohmic resistance. In addition,v it is important that the contact strips be ruggedr and economical.. Due to the frequency with. which tuners are operated, and the large number of contacts used, it is important that the above requirements be met.

The invention to be described hereinafter provides a structure which makes it possible to manufacture and wire a tuner at moderate cost. plained, reference will now be made to the drawing wherein Figure 1 shows a plan view of a tuner embodying the present invention. Figure 2 is an enlarged sectional detail onfline 2-2 of Figgure 1. Figure 3 is a partial top view of a stationary contact strip. Figure 4 is a sectional detail on line 4 4 of Figure 3. Figure 5 is a bottom plan view of the structure of Figure: 3. Figure 6 is a sectional detail on` line 6 -5 of Figure 3. Figure 7 is a perspective detail of a stationary contact part. Figure 8 is a detail of one of the contact strips on the rotor showing one pair of contacts in position. Figure 9 is a sectional detail on line 8 9 of Figure 8 and Figure 10 is a perspective detail of a rotor contact.

The tuner to which this invention pertains comprises frame I of any suitable construction having spiders II and I2 mounted on shaft I3 rotatable in suitable journals in end plates not shown. Shaft I3 carries knob I4 at one end thereof and carries index mechanism I cooperating with stationary index plate I6 at the other end thereof.

Spiders Il and I2 form part of a rotor carrying a number of rotor contact strips 28. As is well known in this type of tuner, each rotor contact strip corresponds to one index position with the rotor generally cooperating With stator contact assembly generally indicated by numeral 22.

Each rotor strip is of suitable insulating inaterial and carries a strip of rotor contacts 24 extending parallel to shaft I3. Each rotor strip 2B, in practice, may have a number of In order that the invention may be exinductauce'A and capacitive elements connected to the series of contact clips and form-ing one or more tuned circuits, all Well known in the art. Statur strip l22 carries a series of stator contacts 25 which are adapted to be engaged by one series of rotor contacts at any one time. The stator contacts are connected to various amplifiers and circuits for cooperation with the tuner circuits in the rotor.

Referring now to the stator strips, this com prises base strip of insulating material extending for the full length of a rotor and anchored to frame I8 in any suitable manner. Each insulating strip 3S has disposed thereon one or more insulating strips 3l. The superimposed insulating strips Sil and t! are provided with a number of registering groups of apertures, each group corresponding to one contact position. Inasmuch. as the various groups are similar. only` one will be described in detail. ThusL the two insulating strips have rectangular aperture 35 symmetrically disposed with respect to the long side of the insulating strips. each side of rectangular aperture 35 are slots` 3`6 to 3'9 inclusive. As is clearly indicated in Figure 3, slots 35 to 39 inclusive have a long side extending transversely of the insulating strips with the slots being disposed generally in line with thev transverse sides of aperture Each group of apertures comprising aperture 35 and slots 3E to 39 inclusive, has a pair of contact members cooperating to form a stator contact clip. Thus referring to Figure 7, one such contact member is shown. This member comprises body 42 having sloping shoulders 43 and 44 with soldering lug 45. Below body 2, the contact clip portion has three depending portions 4l, 48 and 69 respectively. Portions 4l and 49 are for fastening and are similar. Thus portions 4l and 49 are both offset laterally of body 42 at parts 50 and 5I respectively. The offsets for portions 4l and 49 are in the saine direction. Fastening portions 4l and 49 are long enough to extend through a pair of slots such as 36 and 38 for example, with end por tions 52 and 53 protruding beyond two thicle nesses of insulation and being bent along the surface of the insulating plate. Contact portion 48 has a slight offset at 55 in the same d? rection as offsets 58 and 5i. Contact portion 48 has cutout 56 and has active contact portion 58 at the tip shaped as shown in the various figures. Thus contact portion 58 is curved as shown in Figure 5, for example, so that a pair 3 of contact tips 58 provide a sort of hour-glass region between them.

As is clearly indicated in the drawing, a pair of contact clips cooperate to provide a stator contact, the two clips being arranged so that opposite oisets 50 and 5l extend away from each other. Tip portions 52 and 53 of one clip are bent toward the other clip as shown in Figure 6. Thus, a rigid stator contact having a pair of jaws is provided, said contact as a whole providing rigidity in a direction transverse to the mounting strips with resilience in a direction lengthwise of the mounting strips and parallel to shaft I3. Spaced oisets 50 and 5l of each portion of the contact, together with massive shoulders 43 and 44 tend to endow the contacts with great rigidity as well as enabling the contacts to dissipate heat from a soldering iron. Contact portion 4B has substantial spring thereto and makes it possible for a pair of opposed contact members to have good wiping action.

Referring now to the rotor contacts, each pair of stator contact members forming one complete contact unit cooperates with a rotor contact clip shown in detail in Figure 10. This rotor contact clip, generally indicated by numeral 6I, has contact tip 62 having the general shape of a at arrowhead. Head 62 is carried by body 64 preferably somewhat narrower than the base of head 62. Body 64 has a number of spines 65 to 68 inclusive formed thereon, these spines being bent out of the plane or' body 64. Body 64 at the bottom terminates in soldering lug 10.

Each rotor contact member 6I is mounted in a suitably shaped aperture in rotor contact strip 20 of insulating material. ThusV referring specifically to Figure 8, an aperture for a rotor contact clip consists of circular portion 1I With diametrically opposed wings 12 and 'I3 extending transversely of body 20. Each aperture for mounting a contact is so designed that spines 65 to 68 inclusive will lie in wing'sJZ and 13. The transverse dimension of the wings is made small enough so that the spines will bite into the insulating material of which strip `V'Ml is made.

It will be noted that lug portion 1D of a rotor contact has substantially the same width as body portion 64 so that a rotor contact clip may be inserted, lug rst, and pressed home into position. As a rule, heavy copper wires 15 may be disposed in the slot of a soldering lug and prevent the rotor contact from working outwardly.

4 Furthermore, the spines stamped out of the body of the contact prevent the contact from working out. The plane of contact portion 62 of a rotor contact is transverse of the mounting strip so that contact portion 62 may cooperate with a pair of spring jaws in the stator contact assembly.

What is claimed is:

In a turret type high frequency tuner, the combination of a stator contact unitand rotor contact unit, each stator contact unit consisting oi' two similar opposed clip portions, each clip portions comprising a pair of massive shoulder portions and a solder lug portion, said shoulder and lug portions of the two clip portions being adapted to lie against each other, each clip portion having a pair of spaced fastener portions offset transversely away from the other clip portion, each clip portion having a central contact portion, a pair of cooperating clip portions being mounted in an insulating support having a central aperture for the contact jaws and spaced slots for the fastener portions, said fastener portions extending through the insulating support and being bent toward each other, each contact jaw being shaped so that a pair of cooperating jaws provide a generally hour-glass-shaped region, said rotor contact comprising a body portion having a flat arrow-head-shaped portion as the active contact portion at one end and a soldering lug portion at the other end, said body portion having a nurnber of spines formed therefrom, said body and soldering portion being substantially thesame width and said rotor contact being mounted on a rotor insulating support, each rotor contact being insertable in said support lug portion first, said contact portion functioning as a stop for the contact in its travel into the insulating support, said spines being pointed toward the contact portion to prevent withdrawal.

y ALBERT W. ALBRECHT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,670,189 Christie May 15, 192B 1,841,736 Jones Jan. 19, 1932 1,992,806 Benander Feb. 26, 1935 

